Jerry Lewis Heckles Robert De Niro, Martin Scorsese at Tribeca

Robert De Niro and Martin Scorsese conducted a lesson in cheeky film history for a few hundred lucky people this weekend, providing a glimpse into their history working together -- with some help from comedic genius Jerry Lewis.

The trio took the stage to present a remastered version of "The King of Comedy," Scorsese's 1983 classic starring De Niro as a deluded New Yorker devoted to bad jokes and obsessed with celebrity.

The film headlined the Closing Night of the Tribeca Film Festival, an event De Niro co-founded in the wake of the Sept. 11 attacks to aid the revival of downtown Manhattan's economy.

De Niro, Scorsese and Lewis spoke about the making of the film after it screened -- and here's what we learned.

Lewis still loves the attention. While getting more than a few words out of De Niro is a Sisyphean endeavor, Lewis had the crowd (and Scorsese) eating out of the palm of his hand. In addition to making fun of De Niro, he donned a red clown nose, fit an entire glass in his mouth and brought out a rubber chicken. Recalling the shoot for the movie, Scorsese said he suffered endless asthma attacks from laughing. He still finished it, but it took him an extra year.

De Niro has some comedy chops. There's an extended film in the movie that Lewis and De Niro improvised entirely. Lewis said you can tell when you get a script where there's an opening to ad-lib. Even a stuck door was unplanned. "It was so uncomfortable to make that scene," Scorsese said. At one point, Lewis said enough was enough, chiding Scorsese: "Are you going to continue laughing or cut this goddamn scene?"

De Niro doesn't like to watch his own movies. When introducing the film, De Niro said he hadn't seen it in at least 25 years. The audience laughed, but it seems he was serious. His thoughts afterwards? "I can watch a movie 25-30 years after I do it," he said. "I look at it in a different way. Jerry was terrific. This reinforced that for me." So what's next on De Niro's playlist? "Tonight he's gonna see 'Deer Hunter,'" Lewis joked.

Jerry doesn't think Bobby is so terrific. Many have criticized De Niro for coasting after amassing an incomparable body of work in the 1970s and '80s. He has made a series of forgettable thrillers, fending off assailants by reinventing himself in comedies like "Meet the Parents." Lewis joined the chorus of critics. "Did Bobby do a film after this one?" Lewis joked. When De Niro said he had, Lewis quipped back: "I've seen 'em on every plane trip."

Scorsese misses the '70s. Scorsese described "King of Comedy" as marking "the end of a period in filmmaking in Los Angeles." His classic film "Raging Bull," also starring De Niro, opened in theaters 10 days before Michael Cimino's "Heaven's Gate." That film almost ruined United Artists and is blamed for ending the golden age of filmmaking in the '70s. Hollywood executives would no longer grant auteur directors huge budgets for passion projects, often dramas. "That kind of filmmaking went out," Scorsese said. "This was one of the last vestiges of that kind of filmmaking. Everything had changed."

Scorsese misses the '70s Part II. The director consciously avoided camera movements in the film, opting for a "hermetically sealed frame." He felt it was better for comedy, as wide shots would let the physical comedy play out in the frame. "These days now it's different. Cuts are so fast." Cue Michael Bay cackling.

Scorsese's mother never saw De Niro as a movie star. There's a scene in "The King of Comedy" where De Niro's character, Rupert Pupkin, is getting hectored by his mom while putting on a fake show at home. The mother was none other than Scorsese's mom. "She was off-camera," Scorsese said, explaining that the scenes came together naturally, perhaps even improvised. If he brought De Niro or Harvey Keitel around, she saw them as friends of Marty's, not movie stars or even actors. So she would just yell at them, or, to quote De Niro, harangue them. "It was Bobby, she could talk to him that way," Scorsese said.

Lewis wanted to punch Sandra Bernhard in the mouth. There's a scene in the film where Bernhard and De Niro's characters tape Lewis to a seat, covering his entire torso and even parts of his face with masking tape. Lewis felt his character was so angry that "when he gets out of the tape he should punch her right in the mouth." Scorsese was unsure, but Lewis assured him. "She's the reason for birth control." Laughs.

The movie changed Bernhard's life. "It feels like just yesterday that we took over New York City in the summer of '81," the comedienne said in a video message. "Thanks for nothing. Look where I am right now."